Re: DCC Distribution comments, please
Blair & Rasa
See individual responses below. By the way, thank you both for the effort
put into your website, which I've been following for at least two years now,
and for this new group. Just pulling this together so I could ask some
questions has served to both focus my thinking on the bus issues, and
address some misgivings I had.
Regarding PS2012: I prefer to have a power source with eachThey've said in their manual that this is because each booster should have
it's own current protection device, which seems to be why they also include
a Y-adapter (including current limiters) to feed multiple boosters from the
PS2012. Anyway, I'm in your camp for other reasons; home-kitting
half-a-dozen 5-Amp boxes with transformers, fuzes, switches, idiot lights,
and suitable connection means is a no-brainer, and then I know what I've
got, and it's modular; not to mention ease of repair.
Note that the Digitrax command station andyep. And transformers are cheap. I've never seen a schematic for a DCC
booster, but I presume the first input element is a bridge rectifier (this
permits use of either polarity of DC as well as AC for feed - maximizes
robustness); if so, putting a bridge in the transformer chassis would be
redundant unless the transformer chosen is high enough in voltage that we
want to shed a few watts OUTSIDE the booster. BUT, do boosters run cooler
with DC rather than AC input? Does anyone know? It doesn't seem reasonable
from a transformer-diode-filter cap type of power supply point of view, but
I presume they're using switching technology given the size of the box for a
DCS100, so I don't know if there are differences in efficiency between
sinusoid AC and smooth DC input.
Loconet plugs: The only reason to have more Loconet plugs is ifOkay, hadn't considered that, but it's my layout. If I'm willing to
relegate visitors to yard ops unless they bring a radio throttle, that's my
Loconet: There is no practical restriction as to how long your
Feeder length: Feeder lengths of 24" is not advised, but if you canOkay, theory discussion follows. Is it better to put a joint in the
high-current main bus, or a bit more length in the
feeders? Thinking about it, the resistance of a copper-solder-copper joint
has just got to be up there in the same league as several feet of smaller
gauge wire. So unless I'm off-base, and I haven't actually checked this
with the a milli-ohmmeter, it would actually not really matter which way I
went. The primary concern is the coin test, and that's up to me to try. As
far as I'm concerned, any branch in the main bus is at least as much of
concern as multiple feeders, because the main bus joint will see a larger
proportion of the total current being delivered to the loads.
Deep River, Ontario, Canada.
Where there's still 18" of snow in the bush, and a good month for model
railroading before the yardwork begins.